1. Field of the Invention
The present invention relates to an image forming apparatus such as a copying machine, a printer, a recorded image display apparatus or a facsimile which forms a visible image by an electrophotographic system.
2. Description of the Related Art
In a composite machine having copying and printing functions or a facsimile, there is widely used at present time an image forming apparatus of an electrophotographic system, in which a development unit develops a toner image on an image bearing member.
In such an image forming apparatus of an electrophotographic system, it is necessary to prevent the inside the image forming apparatus from being smeared with a toner spattering from the development unit while effectively utilizing space inside the image forming apparatus in order to cope with miniaturization of the image forming apparatus.
There has been known a technique for preventing the inside the image forming apparatus from being smeared with the toner spattering from the development unit, as disclosed in Japanese Patent Application Laid-open No. 11-084793.
In an image forming apparatus disclosed in Japanese Patent Application Laid-open No. 11-084793, a developer storing tray is housed in a space on a side opposite to an image bearing member in the development unit, and further, at a lower portion in a space above a fixing device. The toner spattering from the development unit is stored in the developer storing tray, thereby preventing the inside the image forming apparatus from being smeared with the toner.
However, the technique disclosed in Japanese Patent Application Laid-open No. 11-084793 allows the toner spattering from the development unit to be stored in the developer storing tray, but also permits foreign material other than the toner, such as spattering from members other than the development unit to be stored in the developer storing tray. Members other than the development unit such as a gear train, a development bias contact, an oscillation spring and an adjusting member mostly generate foreign material (e.g., metallic powder). The foreign material, in particular, the metallic powder generated from the afore-mentioned members are deposited on the developer storing tray, and then, the deposited foreign material are carried to the development unit, thereby raising a possibility of a damage exerted on a development sleeve inside the development unit or the image bearing member disposed opposite to the development sleeve.